December in Lappeenranta averages a daily high of -2.1°C with nights around -6.3°C. Expect roughly 15.8 wet days totalling 37mm. A hard month to visit for comfort alone.
Across the year, the best time to visit Lappeenranta is June–August.
Based on LAPPEENRANTA LEPOLA, FI (1.3km), 1995–2024. 17 years of December data.